Mechanism for truing and dressing grinding wheels



J. F. MIRRIELEES MECHANISM FOR TRUING AND DRESSING GRINDING WHEELS Aug. 26 1924. 1,506,655

Filed March 5, 1923 2 Sheets Sheet 1 Aug. 26, 1924. 1,506,655

J. F. MIRRIELEES MECHANISM FOR TRUING AND DRESSING GRINDING WHEELS Filed March 5. 1.923 2 SheetsSheet 2 whee Patented I Aug. 26 1924.

' UNITED STATES PATENT OFFICE.

JAMES F. MIRRIELEES, OF CINCINNATI, OHIO, ASSIGNOR TO THE PRECISION TRUING MACHINE AND TOOL COMPANY, 013 CINCINNATI, OHIO, A CORPORATION OF OHIO.

MECHANISM FOR TRUING AND DRESSING GRINDING WHEELS.

Application filed March 5, 1923. Serial No. 622,888.

To all whom it'may concern:

Be it known that I, J AMES F. MIRRIELEES, a citizen of the United States, residing at Cincinnati, in the county of Hamilton and State of Ohio, have invented certain new and useful Improvements in Mechanism for Truing and Dressing Grinding Wheels, of which the following is a specification.

My invention is an elaboration on the inventions shown, described and claimed in Letters Patent Nos. 1,395,391, 1,395,392, 1,395,393 and 1,395,394, for devices or mechanism for vtruing and dressing grinding wheels, dated November 1,1921, and ranted onners,

on the applications of Edward R. and upon applications for Letters Patent by said Conners for improvements in mechanism for truing and dressing grindin wheels, Serial Nos. 510,7 27 and 510,728, file October 27 1921.

My invention relates to mechanism for truing and dressing grinding wheels, such as emery wheels employed in machinery for rinding or polishing the surfaces of metal 1n precision grinding, and is employable for 'trulng and dressing the ind'ing wheel without removing thegrindlng wheel from the grinding or polishing machine.

It is. the object of my invention to provide a rotary abrading part arranged to contact the grinding surface of a grinding wheel in such manner-as to-cause rotation to be imparted tothe rotary abradingpart by the rotating grinding wheel, and means whereby the speed of rotation of the rotary abrading part. is retarded with relation to the s eed of rotation of the rotar grinding in order to control the neness' of grinding surface of the grinding wheel being treated; further, to provide novel means whereby the rotation of the rotary abrading part is resisted; further, to provide novel means for mounting the rotary abrading part; and, further, to provide novel resilient means hereby to maintain the mandrel an which the rotary abrading part is mounted initstrue ath of movement; further, to provide noveFbraking means for the rotary abrading part; and,.furth er, to rovidenovel means for adjustablysecurmg the rotary abrading part in position in i the machine.

The invention will be further readily understood from the following description and claims, and from the drawings, in which latter:

Fig. 1 is .a plan view of my improved device applied to an exemplified grinding machine, part-1y broken away.

Fig. 2 is across-section of the same taken on the line 22 of Fig. 1, and partly broken away.

Fi 3 is a side elevation of my improvedabra ing device.

Fig. 4 is an axial section of the same taken on the line 4-4 of Fig. 3.

Fig. 5 is an axial section of the same, partly broken away, and taken in the plane of the line 55 of Fig. 4.

Fig. 6 is a detail in'cross-section, taken in the plane of the line 6'6 of Fig. 4.

Fig. 7 is a side elevation of my improved device, partly broken away, and shown in connection with a sectional detail of'the ma-.

chine on which it'is mounted, taken inthe plane of the line 2-2 of Fig. 1; and,

Fig. 8 is an axial section of the same, taken in the plane of the line 8-'8 of Fig. 7.

I have exemplified my invention as em ployed in connection with a so-called grinding or polishing machine employing a rotary grindin grinding or po ishing.

The work to be ground or polished, which may for instance be a shaft, is arranged to be placed between suitable'centers 12, 13,

of which 12 may exemplify a head center, arranged to be rotated by a suitable driving means, as a pulley 14, the usual hill 15 in which the head center is supporte in usual, manner being 'ourna'led in a bearing 16, of a head-stock 1 slidable laterally on guideways 18, 19, of a table 20.

The tail-center 13 is mounted in a suitable sleeve 21, movable. axially in a bearing 22,

wheel 11 for effecting the in usual manner, the bearing being on a rocate axially in planes parallel to the axis of rotation of the shaft of the grinding wheel for grinding or polishing straight work, or the table may be adjusted to an angle with relation to said parallelism, efi'ected, fon'instance, by the gauge 42, and rotation of the handle 43.

I have in the present exemplification illustrated a reciprocating table on which to mount the work, the grinding wheel having a stationary position, although, as explained in the aforesaid patents and applications, the relations of the parts may be reversed, the work bein stationarily positioned and the grinding W eel having reciprocations-imparted to it. I have instanced the abradmg part as acting on the grinding wheel in the absence of work between the centers.

The rotary abrading part is exemplified: It is preferably as anabrading wheel 45; of a texture much harder than the grinding wheel and of much smaller diameter than the diameter of the rinding wheel on which it is to operate. T e rotation imparted to the grinding wheel is instanced as in the direction of the arrow a, while the rotation imparted to the abrading wheel through the medium of the grinding wheel is instanced as in the-direction of the arrow 6.

v The grinding wheel duringoperation becomes impregnated with particles of dirt or metal from the work being operated on, and becomes comparatively glossy and thereby loses its grinding efi'ect, its granular structure also becoming 'dull at the grinding face,

thereby reducing its grinding or polishing,

properties. By means of my invention, the particles of dirt and metal. are removed from the grinding surface of the grinding'whee'l and the recesses and pores in said grinding surface are cleared and the particles or grains of the grinding wheel are sharpened.

The grinding or polishing effect of the grinding wheel is determined by the fineness or coarseness of its grinding surface, and- I have rovidedmeans whereby; toregulate such ne'ne'ss or coarseness in order to dress the grinding wheel according to the work "which. it' is to. perform.

'btain a more marked cleaning and I abrading effect of. the abrading wheel upon the grinding wheel by mounting the abrad tween the ing wheel in such manner that its plane perpendicular to its axis of rotation is at an angle to the plane of the grinding wheel perpendicular to the axis of rotation of the latter. In this manner I obtain an additional swirling action upon the grinding wheel in order to clean the peripheral'interstices or pores of the grinding wheel by brushing or drawing out the dirt or particles chord, indicated by the dotted line 0, to the circle of the grinding wheel intersecting the horizontal plane, indicated by the dotted line d,in which the axis of rotation of the grinding is located, at a slight angle to said horizontal plane, instanced as s1x de ms with the point of intersection e locate between the abrading wheel and the axis of rotation of the grinding wheel, and to locate the contact point of the abrading wheel with the grinding wheel slightly above said horizontal plane.

The nearer the abrading wheel is adjusted into parallelism with the grindin wheel the finer will be the finish imparte 'to the grinding wheel for producing polishing effects on the work, and the greater the an le to which the abrading wheel is adjusted with relation to the grinding wheel, referably not exceeding thirty degrees, t e coarser will be the finish imparted to the grinding wheel for cutting effects upon the work, although I have found that an angular adjustment of substantially fifteen degrees above-mentioned, the adjustment for coarseness or fineness being obtained by the brakflange 52', and is shown clamped to said mandrel by means of a nut 53, a washer 54, for instance of leather, being located begrindlng wheel. and the flange,

and washers 55, 56, the former of leather, 2

being located between the ab-radin 'wheel and the nut, the nut clamping said a rading wheel and washers between the flange and the nut.

A bearing-housing 58 has bearings 59, 60, therein for the mandrel, the bearings be ing shown as combined radial and 'endthrust ball-bearings. The ball-bearing 59 comprises an inner race 61 and an outer race 62. The hearing 60 is shown as comprising an 'inner'race 63 and an outer race 64. The outer races are exemplified as having raceways with single side walls presented toward each othe and are shown fixed in the housing. Th s the race 61 is limited in endw ise direction by an annular shoulder 66 in the housing received about the flange 52, and a tube 67 located between the outer races and forming a separating medium between the same. A nut 68 is threaded into the outer threaded end 69 of the housin this nut being a ring-nut and having en -holes 70 for receiving a suitable wrench' for turnin the nut and clamping the outer races an the separating tube between the shoulder 66 and the nut.

The inner race 61 is received against the flan e 52. A brake-member 73, shown as a w eel, is secured to the mandrel, being shown threaded to an intermediate threaded portion 74 of said mandrel. The brakemember is provided with holes 75 for receiving a suitable wrench. The screwing of the brake-member over the median threaded portion of the mandrel clamps the inner race 61 between it and the flange 52. The outer periphery of this brake-member is shown as an annular braking surface, with which a coacting brake-member, exemplified as a brake-shoe 76, is arranged to act.

A sleeve 81 is received about the reduced portion 82 of the arbor, and has lengthwise or axial movementthereon. The sleeve is shown provided with an annular flange 83 and a threaded end 841- The race 63 is received about the sleeve against said shoulder, a nut 85 bein threaded over the threaded end of the s eeve and arranged for clamping the race 63 between said nut and the annular shoulder 83.

In order to cause combined rotation of the sleeve and the mandrel and permit lengthwise movement between the same, I show the mandrel as provided with a longitudinal slot 86 in which a pin 87 located in the sleeve is received. The nut is provided with suitable holes 88 for receiving a suitable wrench.

A spring 91, shown as a helical spring, is received about the end'of the mandrel. The spring is arranged to exert relative ax'i-al orce in opposite directions upon the mandrel, to which the race 61 is fixed, and the sleeve 81, to which the race 63 is fixed, instanced as an approaching force between sa1d races for causin the balls between the races of the respectlve ball-bearings to be urged toward each other for causing intimate operative contact between said balls and the opposed side walls of the ways in the races, in order to take up wear and to normally cause continuous proper bearing relation in the ball-bearings, whereby vibrations and axial movements of the abrading wheel with relation to the bearinghousing are avoided, and accurate dressin action upon the uiding wheel is assure The spring is s own as a helical spring, the inner end of which bears against the outer end of the nut 85 and the outer end of which bears against an annular shoulder 92 of a nut 93 adjustable over the threaded end 94 of the mandrel. This nut is shown as provided with holes 95 for receiving a suitable wrench. Adjustment of the nut 98 adjusts the distance between the shoul-,

der 92 which is adjustable on the mandrel and the sleeve 81, which is movable axially with relation to the mandrel, causing resilient approach in axial direction between the inner races of the respective ball-bearings, one of which is secured to said mandrel and the other of which is secured to said sleeve, in order to cause resilient approach between the balls of said ball-bearings in axial direction and proper bearing of said balls upon the opposed walls of the racewags in their respective races.

- closing cap 97 is received over the outer end of the bearing-housing, being shown as provided with a threaded stud 98 and an annular flange 99 screwed firmly against the outer end of said bearing-housing. The cap is provided with an inner socket 100 in which the outer end of, the mandrel and the parts mounted thereon are received.

The threads of the threaded portions of the mandrel are preferably such as to be counter to the direction of rotation of the abrading wheel, and are instanced as right hand threads.

A shank 105 is provided for the bearinghousing, and is exemplified as having a taper end 106 received in a taper socket 107 of the bearin housing, and is provided with a threa ed end 108 received in a threaded socket 109 in the bearing-housing. The turning of the shank in said sockets rigidly connects the bearing-housing and the shank.

The shank is exemplified as having a bore 111, in which a stem 112 is received. The brake-shoe 76 has connection with the inner end of the stem, for controlling the braking F of the stem, and the outer end of the bore is provided with a threaded portion 118. A

nut 119 is adjustable in the threaded portion and may be turned by a suitable wrench received in slots 120 in said nut. A spring 121 surrounds the stem between the nut and the shoulder. Adjustment of the nut regulates the tension of the spring and consequently the force of application of the brakeshoe to the coacting brake-member on the mandrel.

A quick-release device is provided for the braking means, and is instanced as a handle 125, provided at the outer end of the stem, being shown pinned thereto by a pin 126. The handle is provided with lugs 127 received in slots 1281 in the shank. The lugs and slots are preferably of such length that considerable movement of the stem is permltted so as to accommodate for firm ap lication of the brake-shoe upon the coactlng blil'ake-member and for wear of the brakes oe.

The lugs are received in the slots when the releasable braking member, instanced as the brake-shoe, is applied to its coacting brakemember, or the lugs may be arranged crosswise of the slots and contact the outer end of the shank. for relieving the braking contact between the braking members, and releasing said releasable braking member from the pressure of the spring 121.

Adjustment of the spring 121 adjusts the force of application of the brake-shoe on its coacting brake-member, this resistance being communicated as a resistance to rotation of the abrading wheel at the meeting faces between the abrading wheel and the grinding wheel which is being operated on. The greater this resistance the coarser will be the dressing effect upon the grinding wheel. When the brake-shoe is relieved from its coacting brake-member, more ready rotation of the abrading wheel by means of the grinding wheel takes place, resulting in a finer dressing or finish being applied to the grindingwheel. Adjustment of the nut 119 adjusts the fineness or coarseness of resulting action of the abrading wheel on the grinding wheel. Relief of braking action is obtained by means of operating the outer handle 125.

I have profided means for readily affixing the abrading means to the grinding or polishing machine. The table of the grinding or polishing machine is in the present in stance provided with a guide 131 and a rail 132. A clamp 133 is provided with ajaw 134 co-acting with the guide and a clamping means comprising a jaw 136 having an inclined face 137 on the body of the clamp and a clamp-plate 138, the inclined face and the clamp-plate being arranged to clamp upon the rail 132.

A stem 141 is located in a bearing 142 of the clamp and is held non-rotative therein by being provided with a groove 143, a pm 144 in the body of the clamp being received in said groove. An adjusting nut 145 and a lock-nut 146 are received over the threaded end 147 of said stem. The head 149 of said stem is shown as a flat head, a fork 150 of a handle 151 being received about said head and articulated therewith by means of a pin 152. The body of the clamp has a socket 153 in which there is a spring 154 surrounding said stem, normally exerting separating movement between the bottom of the socket and theclamp-plate 138.

A cap 156 is provided with a slot 157 through which the head of the stem is received. The inner end of the fork 150 is provided with cams 159 and shoulders 160,

arranged to bear against said cap, and to cause clamping movement between said cap and the clamp-plate 138 at one side of the rail 132 and the inclined face 137 at the other side of said rail, causing clamping of the jaw 138 upon the rail 132. Rotation of the clamp-plate 138 on the stem is prevented by means of a pin 161 fixedin the body of the clamp and received in a hole 162 in said clamp-plate.

The body of the clamp is provided with a bearing 165, shown as a clamp-bearing, in which the shank 105 is received, and in which said shank may be adjusted axially and rotatively, for locating the periphery of the abrading wheel in correct relation to' the periphery of the grinding wheel. When such adjustment has been made, the clamp bearing is clamped about the shank by means of the bolts 166, journaled in holes 167 of a cheek 168 and threaded in threaded holes 169 of a cheek 170, the cheeks being located at the respective sides of a split 171 1n said clamp-bearing, which is thereby constltuted a split-bearing. The bearing-housing 58 is provided with a protective flange 175 jpr the abrading wheel.

The bearing-housing is exemplified as an oil casing for inclosing a body of oil for 011- ing the ball-bearings and mlovable parts within the housing. A felt washer 176 is clamped between the end of the housing and the washer 54 of the abrading wheel for preventing leakage of oil, the oil being further retained in said housing by means of the closing cap 97. A felt washer 177 filling the bore in the shank 105 and held against the shoulder 118 by means of a metal washer 178 clamped upon said felt washer by the spring 121, retains the oil in the shank. The oil may be supplied into the housing through a hole 179 closed by a cap 180 and communicating with an oil groove 181 extending lengthwise throughout the outer periphery of the tube 67.

My improved device provides ready, economical and compact means for producing truing and dressing efiects upon the grinding wheel, without removing the same from the grinding or polishing machine, provides ready means for adjusting the fineness or coarseness of the grinding surface of the grinding wheel by means of the adjustment of inclination of the plane of the abrading wheel with relation to the plane of the Letters Patent, is:

1. lln mmha'nism for truing and dressing grinding wheels, the combination of a normally quiescent rotary abrading part for coaction with a rotary, rinding wheel, a support for said rotary abrading part comprising a shank, ata-ble comprising a guide and a rail, and a clamp comprising a bearing for said shank and clamping means, means for permitting ad'ustment of said shank in said bearing, sai clamping means comprising a jaw for coaction with said guide and a movable 'aw, a spring normally retracting said movable'jaw, and a handle comprising a cam for clamping said movable jaw to said rail.

2. In mechanism for truing and dressing grinding wheels, the combination of a normally quiescent rotary abrading wheel, a support therefor comprising means for angular adjustment of the plane of said rotary abrading wheel with relation to the plane of the grinding wheel, and braking means for said abrading wheel.

3. In mechanism for truing and dressing grinding wheels, the combination of a normally quiescent rotary abrading wheel, a support therefor comprising means for angular adjustment of the plane of said rtary abrading wheel with relation to the plane of the grinding wheel, braking means for said abrading wheel and adjusting means for controlling the braking efi'ect of said brakin means.

4. lln mec anism for truing and dressing grinding wheels, the combinationof a normally quiescent rotary abrading wheel, a support therefor comprising means for angular adjustment of the lane of said rotary abrading wheel wit relation to the plane of the grindin wheel, braking means for said abrading w eel, and quick' release means for said braking means.

5. In mechanism for truing and dressing grinding wheels, the combination of a normally quiescent rotary abrading art, a mandrel therefor, opposed hearings or said mandrel, and resihent means operatively disposed between said bearings for causing resilient axial take-up movement between said bearings.

6. In mechanism for truing and dressing grinding wheels, the combination of a normallv quiescent rotary abrading part, a mandrel therefor, opposed bearings for said mandrel, resilient means operatively disposed between said bearings for causing resilient axial take-up movement between said bearings, and braking means for said mandr el.

7 In mechanism for truin'g and dressing grinding wheels, the combinationof a normally quiescent rotary abrading part, a mandrel therefor, opposed bearings for said mandrel, resilient means operatively disposed between said bearings for causing resilient axial take-up movement between said bearings, braking means for said mandrel, and means for adjusting said braking means.

8. lln mechanism for truing and dressing grinding wheels, the combination of a normall uiescent rotary abrading part, a mandrel therefor, opposed bearings for said mandrel, resilient means operatively disposed between said bearings for causing resilient axial take-up movement between said bearings, braking means for said mandrel, and quick release means for said braking means.

9. lln mechanism for truing and dressing grinding wheels, the combination of a normally quiescent rotary abrading part, a mandrel therefor, opposed ball-bearings for said mandrel respectively comprising opposed races, means for ositioning one or the races of one of said hall-bearings, a part movable axially with relation to the mandrel, means for securing a race of the other of said ball-bearings to said art, and sprin means operatively dispose between sai part and said mandrel arran ed for axial take-u movement in said ballarings.

10. n mechanism for-truing and dressing grinding wheels, the combination of a normally qulescent rotary abrading part, a mandrel therefor, spaced-apart bearings for said mandrel, an annular braking part on said mandrel between said bearings, and a coacting braking part for said annular braking part.

11. In mechanism for truing and dressing ding wheels, the combination of a normall uiescent rotary abrading part, a man re therefor, a spaced-apart bearings for said mandrel, an annular braking part on said mandrel between said bearings, a coacting braking part for said annular braking part, and resilient means for said coacting braking part to urge braking fi'iction on sald first-named braking part.

12. In mechanism for truing and dressing grinding wheels, the combination of a normally uiescent rotary abrading part, a mandre therefor, spaced-apart bearings for said mandrel, an annular braking part on said mandrel between said bearings, a coacting braking part for said'annular braking part, resilient means for said coacting braking part to urge braking friction on said first-named braking part, and means for adjustin said resilient means.

13. In mec anism for truing and dressing grinding wheels, the combination of a normally quiescent rotary abrading part, a mandrel therefor, spaced-apart bearings for said mandrel, an annular braking part on said mandrel between said bearings, a coacting braking part for said annular braking part, resilient means for said coacting braking part to urge braking friction on said firstnamed braking part, and quick release means for said coacting braking part.

14. In mechanism for truing and dressing grinding wheels, the combination of a normally quiescent rotary abrading part, a mandrel therefor, a pair of ball-bearings for said mandrel, an annular braking part on said mandrel, means for holding the inner race of one of said ball-bearings to said mandrel, a sleeve axially movable on said mandrel, means for holding the inner race of the other of said ball-bearings to said sleeve, a spring operatively disposed between said sleeve and said mandrel, and p0- sitioning means for the outer races of said ball-bearings.

15. In mechanism for truing and dressing grinding wheels, the combination of a normally quiescent rotary abrading part, a mandrel therefor, a bearing-housing, ballbearings in said housing for said mandrel, spring means in said housing urging axial take-up movement in said ball-bearings, and braking means in said housing for said mandrel.

16. In mechanism for truing and dressing grinding wheels, the combination of a normally quiescent rotary abrading part, a mandrel therefor, a bearing-housing, ballbearings in said housing for said mandrel, sprmg means in said housing urging axial take-up movement in said ball-bearings, braking means in said housing for said mandrel, a shank for said housing, and brake control means supported by said shank.

17. In mechanism for truing and dressing grinding wheels, the combination of a normally quiescent rotary abrading part, a mandrel therefor, a bearing-housing for said mandrel, a pair of ball-bearings for said mandrel in said housing, a tube separating the outer races of said ball-bearings, means for securing said outer races in said housing, a sleeve about said mandrel, means for securing the inner races of said ball-bearings respectively to said mandrel and to said sleeve, and a spring causing axial take-up movement between said mandrel and said sleeve.

18. In mechanism for truing and dressing grinding wheels, the combination of a normally quiescent rotary abrading part, a mandrel therefor, a bearing-housing for said mandrel, a pair of ball-bearings for said mandrel in said housing,,a tube separating the outer races of said ball-bearings, means for securing said outer races in said housing, a sleeve about said mandrel, means for securing the inner races of said ball-bearings respectively to said mandrel and to said sleeve, a spring causing axial take-up movement between said mandrel and said sleeve means on said mandrel for adjusting said spring, and a hollow cap for said housing receiving said last-named means.

19. In mechanism for truing and dressing grinding wheels,the combination of a normally quiescent rotary abrading part, a mandrel therefor, a bearing-housing for said mandrel, a shank extending from the latter, a pair of ball-bearingsfor said mandrel in said housing, separating means in said housing for the outer races of said ball-bearings, means for securing said outer races in said housing, a sleeve about said mandrel, means for securing the inner races of said ballbearings respectively to said mandrel and to said sleeve, a spring about said mandrel causing axial take-up movement between said mandrel and said sleeve, an annular brake-member on said mandrel in said tube, a brake-shoe for said brake-member, and a stem in said shank for said brake-shoe.

20. In mechanism for truing and dressing grinding wheels, the combination of a normally quiescent rotary abrading part, a mandrel therefor, a bearing-housing for said mandrel, a shank extending from the latter, a pair of ball-bearings for said mandrel in said housing, separating means in said housing for the'outer races of said ball-bearings means for securing said outer races in said housing, a sleeve. about said mandrel, means for securing the inner races of said ballbearings respectively to said mandrel and to said sleeve, a spring about said mandrel causing axial take-up movement between said mandrel and said sleeve, an annular brake-member on said mandrel in said tube, a brake-shoe for said brake-member, a stem in said shank for said brake-shoe, a spring for said stem, and means between said shank and said spring for adjusting said spring;

21. In mechanism for truing and dressing grinding wheels, the combination of a normally quiescent rotary abrading part, a mandrel therefor, a bearing-housin for said mandrel, a shank extending from t e latter, a pair of ball-bearings for said mandrel in said housing, separating means in said housing for the outer races of said ball-bearings, means for securing said outer races in said housing, a sleeve about said mandrel, means for securing the inner races of said ballbearings respectively to said mandrel and to said sleeve, a spring about said mandrel causing axial take-up movement between In-testimony whereof, I have hereunto said mandrel and said sleeve, an annular signed my name in the presence of two subbrake-member on said mandrel 1n said tube, scriblng Witnesses.

a brake-shoe for said brake-member, a stem JAMES F. MIRRIELEES. 5 in said shank for said brake-shoe, and quick I Witnesses:

release means on said stem for said brake- EDWARD J. BRIGGS,

shoe. DELMA Wnnnsme. 

